The doctrine of the work of Christ is central to understanding our salvation from sin, death, and the wrath of God. The holiness of God and the sinfulness of man mean that human beings need redemption and reconciliation to God. The work of Christ is prefigured in the Old Testament, first received by God’s old covenant people, by means of sacrifices, types and shadows, events, and prophecy. In the old covenant, God instituted the sacrificial system wherein He revealed that sacrifices had to be made for human beings to be forgiven and reconciled to Him. These sacrifices pointed to various aspects of the saving work Christ accomplished on the cross. The prophets foretold the work of the Messiah by language of judgment and restoration, sacrifice and atonement, and humiliation and exaltation. The three offices of leadership in theocratic Israel also directed attention to the work of Christ in His threefold office of Prophet, Priest, and King of the church.
In the history of the development of Christian dogma, the doctrine of the work of Christ differs from the doctrine of the Trinity or the person of Christ in that no theological controversy about Christ’s work led to an early church council and a definitive creed that confesses what exactly the work accomplished. Formulations expositing the work of Christ in detail came much later, particularly in the Protestant Reformation.
The work of Christ is so multifaceted that theologians have sometimes focused on different aspects of it—while agreeing that the central work of Jesus was His sacrificing Himself to God. Fallen in Adam, mankind has lost communion with God and is by nature under His wrath and curse. This means that something had to be done in order for fallen image bearers to be reconciled to God. The sinfulness of mankind necessitated the saving work of the Redeemer. The eternal Son of God became incarnate in the fulness of time to redeem God’s people from their sins (Matt. 1:21). Everything about His saving work must be understood in light of our need for redemption. Immediately after the fall of Adam, we discover that sacrifice is a God-appointed remedy for the breached relationship and loss of communion. God Himself killed an animal and clothed Adam and Eve with its skins. Abel sacrificed a lamb to God. Noah and Abraham offered animal sacrifices on behalf of themselves and their families. All these pointed to the need for a sacrificial substitute who would take the wrath that mankind deserves in order to reconcile men to God.
The Passover lamb is the first of the sacrifices instituted in the formal system of worship given to old covenant Israel. The Lord passed by in judgment those Israelites who sacrificed a lamb and placed its blood on the doorposts of their houses in Egypt. Later in the New Testament, we read that Jesus is the fulfillment of this symbolic and typical sacrifice (Ex. 12:46; John 19:36; 1 Cor. 5:7). The subsequent Old Testament sacrificial system foreshadowed Christ’s saving work by showing in vivid detail the need sinners have for a substitutionary sacrifice that provides expiation and propitiation. The language of Isaiah’s prophecy of the Suffering Servant includes the language of sacrifice (see Isa. 53:7)—thereby indicating that the Messiah would be the final and perfect substitutionary sacrifice. In “The Christ of the Three Appearings,” Sinclair Ferguson explains the role of old covenant Israel’s sacrificial system in redemptive history: “Old covenant believers lived in the light of the promises of God and walked by faith trying to understand the inner significance of the sacrifices God had provided. They looked at the sacrificial system to the real, final sacrifice that they typified. They did not receive what God had promised (Heb. 11:39). Yet, at the same time, they understood that the pattern of repeated sacrifice of animals, by a long line of priests who needed to atone for their own sins, could not be the way of full and final forgiveness (Heb.9:6–10;10:1–4).”
In addition to the sacrificial system, the old covenant feasts and festivals of Israel foreshadowed aspects of the saving work of Christ. Additionally, Israel’s conquest of Canaan and the ongoing conflict between the covenant people and the pagan nations reveal elements of the saving and sanctifying work of Christ on the cross.
Theologians have frequently categorized the saving work of Christ as occurring in His states of humiliation and exaltation. Dr. R.C. Sproul explains that “the states of Christ refer to Christ’s role or activity at various times throughout His life and existence.” The idea of sacrifice carries with it the idea of humiliation. Isaiah spoke of the Suffering Servant of the Lord in terms of His humiliation and abasement: “He was despised and rejected by men, a man of sorrows and acquainted with grief; and as one from whom men hide their faces he was despised, and we esteemed him not” (Isa. 53:3). Theologians have also emphasized that the whole of Jesus’ life and ministry are marked by humiliation. As the Westminster Shorter Catechism explains, “Christ’s humiliation consisted in his being born, and that in a low condition, made under the law, undergoing the miseries of this life, the wrath of God, and the cursed death of the cross; in being buried, and continuing under the power of death for a time” (Q&A 27).
The Apostle Paul highlights the aspect of Christ’s obedience when he speaks of the humiliation of the eternal Son of God, saying that Christ “humbled himself by becoming obedient to the point of death, even death on a cross” (Phil. 2:6–8). The obedience of Jesus is an essential aspect of His saving work. Jesus was “born under the Law” (Gal. 4:3) in order to keep the righteous requirements of the Law of God for those He would redeem. His law-keeping is counted to believers as their law-keeping, since He acts as the covenant-keeping representative of His people. Jesus is the Law-keeping last Adam and true Israel of God. He is also the curse-bearing Redeemer of the elect. His sacrifice had to be a sinless sacrifice to be acceptable to God and efficacious for the forgiveness of the sins of His people. On the cross, the sinless Son of God took the sin of His people on Himself so that He could impute to them His righteous status before God. Theologians call this “the great exchange.” This aspect of the work of Christ is the basis of the biblical and Reformed doctrine of justification.
The work of Christ in His state of exaltation is immediately followed by His work in the state of humiliation. In His resurrection, Jesus became the firstborn from the dead, the head of the new creation, and the reigning Redeemer of humanity. The Westminster Shorter Catechism explains the nature of Christ’s work in His state of exaltation when it says, “Christ’s exaltation consists in his rising again from the dead on the third day, in ascending up into heaven, in sitting at the right hand of God the Father, and in coming to judge the world at the last day” (Q&A 28). When He comes again, Jesus will bring about the consummation of all things—the regeneration of the cosmos. In the new heavens and new earth, He will reign as the glorified and exalted head of the new humanity.
Jesus accomplishes His saving work by filling the threefold office of Prophet, Priest, and King in His estates of humiliation and exaltation. God ordained these three offices in the old covenant to reflect particular elements of what the promised Messiah (literally, “Anointed One”) would accomplish in His person and by His work. Some individuals filled more than one of these offices during the old covenant era. For instance, Melchizedek functioned as both a king and a priest (Gen. 14). David filled the office of a prophet and a king. Some priests acted as prophets. For instance, Zechariah, John the Baptist’s father, prophesied during his time of temple service as a priest. Nevertheless, these offices were established on account of the Lord Jesus Christ, who fills all three offices as the Messiah.
Each of the three offices had a distinctive divinely instituted purpose. A prophet represented God to men by revealing God and His will to His creatures. A priest represents man before God by sacrificing on behalf of the people and interceding for them before God. A king represents both God and man by exercising God’s righteous rule in subduing God’s people to Himself and by conquering all His and their enemies.
As Prophet, Jesus reveals God to mankind. He teaches God’s will to His people. The Westminster Shorter Catechism summarizes Christ’s work as prophet: “Christ executes the office of a prophet, in revealing to us, by his word and Spirit, the will of God for our salvation” (Q&A 24). In His own person, Jesus carries out the prophetic ministry. He is the eternal Word made flesh (John 1:1, 14). He speaks with the divine authority of God, since He is God and always spoke what He heard from His Father. Whereas the Old Testament prophets began their prophetic oracles with the introduction “Thus says the Lord,” Jesus often introduced the revelation of God’s Word with the words “Truly, truly, I say to you” (John 1:51; 3:3; 5:19, 24; 6:26, 32, 47, 53; 8:34, 51, 58; 10:1, 7; 12:24; 13:16, 20; 14:12; 16:20, 23).
As the Great High Priest of the church, Jesus sacrificed Himself to atone for the sins of His people and then ascended to the right hand of the Father, where He ever lives to make intercession for them. Heidelberg Catechism 31 states that Christ is “our only high priest, who by the one sacrifice of His body has redeemed us, and ever lives to make intercession for us with the Father.” His sacrifice is a propitiation that satisfies God’s wrath and justice in our place. It is also an expiation that cleanses us from the guilt of sin. When theologians refer to the “finished work of Jesus,” they commonly have his once-for-all sacrifice in mind. However, the prayers of Jesus constitute a central part of His ongoing work. These two sides of His saving work were foreshadowed in the work of the high priest in the tabernacle and temple in Israel in the old covenant.